Their marketing study found that cell phone users are less likely to volunteer for community service.

The cell phone users were also less persistent in solving word problems – even though they knew their answers would translate to a monetary donation to charity.
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The authors cited previous research in explaining a root cause of their findings: “The cellphone directly evokes feelings of connectivity to others, thereby fulfilling the basic human need to belong.” This results in reducing one’s desire to connect with others or to engage in empathic and prosocial behavior.

The study was done on college students in their early 20s, but “the researchers think the findings would apply to any group,” according to Times.